Cancer, irrespective of its pathogenesis, is characterized by uncontrolled growth and survival of cells. Common to most forms of cancer is an error in the cellular mechanism responsible for balancing cell survival and cell death.
According to the American Cancer Society, lung cancer is the leading cause of cancer death for both men and women. Small cell lung cancer (SCLC) accounts for approximately 20% of all lung cancers. The 5-year survival rate for small cell lung cancer is about 15%.
Certain thiosemicarbazones, such as those disclosed in British Patent No. 1,026,401, International Patent Application No. WO2004/066725, Japanese Patent No. 56-95161 and U.S. Pat. No. 4,927,843, have been used to treat, for example, a variety of viruses. Other thiosemicarbazones, however, may be used to treat cancer. French Patent No. 2,879,194 is directed to certain thiosemicarbazones that may be used in the treatment or prevention of cancer, in dermatological treatment, in the treatment of cardiovascular and immune diseases, lipid-metabolism related diseases and modulate PPAR's. International Patent Application No. WO 2006/009765 is directed to specific thiosemicarbazones that may be used in anti-cancer therapy that mitigates the development of drug resistance. U.S. Pat. No. 4,593,027 is directed to hydrazone derivatives that may be used as a chemotherapeutic.
Chinese Patent Application No. 1891701 is directed to a thiosemicarbazone, which are anti-tumour drugs. Chinese Patent Application No. 1907970 is directed to the synthesis of heteroaryl thiocarbonyl compounds. International Patent Application Nos. WO 01/34585 and WO 02/49413 encompass compounds that are thiosemicarbazones, which are used for thrombopoietin mimetrics. International Patent Application No. WO 2004/099371 is directed to thiosemicarbazones that treat ischemia-related conditions. International Patent Application No. WO 2005/087211 is directed to thiocarbazone compounds that are anti-parasitic and inhibit cellular replication associated with cancer cells.
There is a need, however, for new therapeutic drug treatments to treat cancers more effectively and/or with reduced toxicity, particularly lung cancer.